Artículos de Investigación

Permanent URI for this communityhttps://bibliorepositorio.unach.cl/handle/123456789/704

Browse

Search Results

Now showing 1 - 7 of 7

Some of the metrics are blocked by your
consent settings
Chewing Index: A Pilot Trial to Measure Masticatory Effort
(2026)
Franco Marinelli
;
Camila Venegas-Ocampo
;
Josefa Alarcón-Apablaza
;
Rosemarie Schneider
;
Pablo Navarro
<jats:p>Background/Objectives: Population aging presents new challenges for achieving healthy aging. Edentulism is a condition that diminishes quality of life. Several studies have attempted to analyze the impact of edentulism on masticatory function either by evaluating the final stage of the food bolus or the masticatory process itself. The present study aims to develop a chewing index (Ci) based on chewing time, the number of cycles, and the muscular activity of the masseter and temporal muscles. Methods: Two groups (n = 10 each, 60–80 years old), one with functional dentition (21 or more teeth) (Group F) and one with complete denture wearers (Group D), were used. Participants were asked to chew a total of 36 food samples. The number of chewing cycles (N), chewing time (T), and bilateral activity of the masseter and anterior temporal muscles were recorded and quantified using the root mean square. This activity was normalized with respect to a 5 s maximum voluntary clenching (TMAV). A chewing index (Ci) was calculated using the equation Ci = N × V%¯ × T/TMAV, where V%¯ represents the average normalized activity of the four muscles. Results: Ci values ranged from 0 to 62 for Group F and 0 to 262 for Group D. For 15 out of the 36 food samples, Ci was higher in Group D than in Group F. Conclusions: The results of this study are consistent with previous research showing that complete denture wearers must chew for a longer time and perform a greater number of chewing cycles compared with subjects with functional dentition.</jats:p>
Some of the metrics are blocked by your
consent settings
Evaluation of Mandibular Border Movements and Mastication in Patients with Temporomandibular Disorders: A Pilot Study with 3D Electromagnetic Articulography and Surface Electromyography
(2025)
Camila Cerda
;
Franco Marinelli
;
Jarpa-Parra, Marcela
;
Pablo Navarro
;
Ramón Fuentes
Temporomandibular disorders (TMD) are characterized by pain and restricted functionality of the temporomandibular joint (TMJ). The objective of this study was to characterize the kinematic and electromyographic patterns of mandibular border movements and mastication in patients with different forms of TMD compared with healthy controls, through a simultaneous three-dimensional electromagnetic articulography (EMA-3D) and surface electromyography (sEMG) recording protocol. Sixteen participants were included and divided into three groups according to the TMD diagnosis (articular, muscular and mixed) and one healthy control group. Kinematic data were recorded using EMA-3D, and electromyographic activity of the masticatory muscles was assessed using sEMG. Variables analyzed included trajectories, areas, ranges, and electrical activity during mandibular border movements and mastication. Patients with TMD exhibited reduced movement trajectories but larger areas within the mandibular polygons, particularly in the frontal and sagittal planes. During mastication, the number of cycles was higher in the muscular group and lower in the healthy controls. Patients with TMD showed greater mean electromyographic activity, which could suggest compensatory muscle strain. The EMA-3D system provided an accurate threedimensional analysis, while sEMG captured detailed patterns of muscle activation and strain, that help better understand the neuromuscular alterations associated with TMD. Differentiation between TMD types (articular, muscular and mixed) for the study of its kinematic and electromyographic characteristics, is essential to improve diagnosis and treatment strategies. This study highlights the relevance of advanced tools such as EMA-3D and sEMG in the evaluation of TMD using a simultaneous recording protocol such as the one proposed in this study.
Some of the metrics are blocked by your
consent settings
Análisis Cinemático de la Masticación de una Granola Prototipo en Contraste con la Masticación de Maní
(2020)
Constanza Farfán
;
Joel Jerson Coaquira-Quispe
;
María Florencia Lezcano
;
Alain Arias
;
Pablo Navarro
La masticación se ha estudiado desde diferentes puntos de vista, utilizando alimentos de prueba naturales y artificiales. La evidencia es escasa cuando se analizan alimentos a base de cereales, que van desde cereales para el desayuno hasta barras de granola. El investigar este tipo de alimentos, se vuelve importante para entender el comportamiento de la masticación frente a alimentos con diferentes composiciones y texturas, y como estas características pueden influir en el proceso masticatorio. Se analizó la masticación desde un punto de vista cinemático, en sujetos jóvenes dentados. El alimento de prueba utilizado fue granola prototipo y maní, este último se ha estudiado en sujetos con rehabilitación protésica y su consumo se recomienda en esta población. Se analizaron las características cinemáticas de la masticación como numero de ciclos, frecuencia masticatoria, velocidad de masticación de ascenso y descenso, y el área de masticación en los tres planos del espacio. Se relacionaron los movimientos masticatorios con los movimientos mandibulares bordeantes que conformaron el polígono de Posselt, este también se analizó en los tres planos espaciales. En todas las variables analizadas la granola presento valores mayores, excepto en el número de ciclos masticatorios, sólo se encontraron diferencias estadísticamente significativas (p= 0,03) al comparar la velocidad (ascenso y descenso) y el área de masticación en el plano horizontal.
Some of the metrics are blocked by your
consent settings
Characteristics of Mandibular Movement and Mastication in Older Adults with Removable Dental Prostheses: Three-Dimensional Analysis
(2020)
Paloma Rivera
;
Constanza Farfán
;
Alain Arias
;
María Florencia Lezcano
;
Fernando José Dias
Aging is a dynamic process that includes various alterations in the oral cavity, with tooth loss being the most frequent. Rehabilitative treatment may include removable or fixed prostheses and implants. The aim of this study was to describe the geometric (trajectory, ranges, areas) and kinematic (speed) characteristics of the mandibular and masticatory movements threedimensionally in participants with dental prostheses. A sample of 10 participants with removable prosthetic rehabilitation was divided into three groups (complete, atypical and overdenture) the characteristics of mandibular movements bordering and chewing with 3D Electromagnetic Articulography were measured. The Posselt polygonin was obtained, the frontal and sagittal plans, its areas, trajectories and ranges are analyzed. The masticatory movements were analyzed in the area of each cycle, the frequency, the speed and the reason between the masticatory cycle and the bordering movements, no significant differences between the groups. Subjects with dental prostheses, regardless of the type, they showed low of motion (border and functional) compared to dentate subjects with no functional alterations whose values have been reported in the literature. The subjects with overdenture have values closer to what is described for young dentate subjects.
Some of the metrics are blocked by your
consent settings
A New Tridimensional Insight into Geometric and Kinematic Characteristics of Masticatory Cycles in Participants with Normal Occlusion
(2018)
Ramón Fuentes
;
Alain Arias
;
María Florencia Lezcano
;
Diego Saravia
;
Gisaku Kuramochi
<jats:p>The aim of this study was to analyze the general, geometric, and kinematic characteristics of the masticatory cycle’s movements in a tridimensional way, using a method developed by our study group to provide a new insight into the analysis of mandibular movements due to advancement in the potential of computational analysis. Ten individuals (20.1 ± 2.69 years), molar class I, without mandibular movement problems participated in this study. The movements of the masticatory cycles, frontal and sagittal mandibular border movements, were recorded using 3D electromagnetic articulography and processed with computational scripts developed by our research group. The number of chewing cycles, frequency (cycles/s), chewing cycle areas/mandibular border movements areas ratios, and the mouth opening and closing speeds on the 3D trajectory of the chewing cycle were compared. The cycles were divided and analyzed in thirds. The masticatory cycles showed high variation among the individuals (21.6 ± 9.4 cycles); the frequency (1.46 ± 0.21 cycles/s) revealed a moderate positive correlation (R = 0.52) with the number of cycles. The frontal area ratios between the cycle area and the mandibular border movement presented higher values in the first third (6.65%) of the masticatory cycles, and the ratios of sagittal areas were higher and more variable (first, 7.67%; second, 8.06%; and third, 10.04%) than the frontal view. The opening and closing mouth speeds were greater in the second third of the masticatory cycles (OS, 57.82 mm/s; CS, 58.34 mm/s) without a significant difference between the opening and closing movements when the same thirds were evaluated. Further studies are necessary to improve the understanding of the masticatory cycles regarding the standardization of parameters and their values.</jats:p>
Some of the metrics are blocked by your
consent settings
Índices de Simetría Condilar y Mandibular a Través de Radiografías Panorámicas Digitales en una Muestra de Pacientes Chilenos
(2018)
Ramón Fuentes
;
Manuel Arellano-Villalón
;
Natalia Soto-Faúndez
;
Fernando J Dias
;
Pablo Navarro
La simetría mandibular puede alterarse por diversos motivos. Variados estudios buscan definir parámetros de “normalidad” y para ello se han descrito técnicas que utilizan la radiografía panorámica (RPN). El objetivo de este estudio fue determinar índices de simetría mandibular/condilar en una muestra de pacientes chilenos. Se realizó un estudio descriptivo de corte trasversal en RPN digitales obtenidas de la Clínica Odontológica de la Universidad de La Frontera. Se aplicaron criterios de inclusión: pacientes mayores de 18 años, dentición permanente completa hasta el primer molar; y de exclusión: signos radiográficos de alteraciones óseas y/ o cirugía mandibular, cóndilos no visibles, ortodoncia. Se utilizó el software ImageJ para dibujar rectas y medir la altura de la rama y cóndilo mandibular del lado derecho e izquierdo de acuerdo a la técnica propuesta por Kjellberg et al. (1994). Con estas medidas se calculó el índice de simetría entre altura condilar y rama (S1); y entre altura condilar y mandibular (S2). 235 RPN digitales fueron analizadas (95 hombres; 140 mujeres) con edad promedio de 24,98±7,32 años. El promedio de S1 fue de 93,74 % (±3,85) en hombres y 93,41 % (±5,77) en mujeres, mientras que para S2 fue de 90,50 % (±6,51) en hombres y 90,27 % (±7,80) en mujeres, sin diferencias significativas para ninguno de ambos índices (p=0,347 y p=0,233, respectivamente). En cuanto a la edad, tampoco se encontraron diferencias significativas en el promedio de los índices S1 y S2 para cada rango etario (p=0,594 y p=0,669, respectivamente). Mediante este estudio se concluye que hay un alto porcentaje de pacientes con simetría mandibular/condilar en ambos sexos y en diferentes rangos etarios, esto sin considerar el estado de salud o presencia de alteraciones morfológicas y/o funcionales.
Some of the metrics are blocked by your
consent settings
Morphological variations of the mandibular canal in digital panoramic radiographs: a retrospective study in a Chilean population
(2018)
Ramón Fuentes
;
Alain Arias-betancur
;
Constanza Farfán
;
Nicolás Astete
;
Ivonne Garay
Background: Morphological variations of the mandibular canal (MC) have been described in literature, so the clinician must be able to recognise them and adapt their treatment accordingly. The aim of this study was to determine the prevalence of morphological variations of the MC using digital panoramic radiographs (DPR) of Chilean patients. Materials and methods: A retrospective study in which 1400 DPR were analysed to identify cases of bifid, trifid and retromolar MC. The radiographs were analysed independently by two examiners who had previously been trained by a specialist in oral and maxillofacial radiology. Inclusion and exclusion criteria were applied to reach a final sample. Results: Nine hundred and twenty-five radiographs were included (599 female, 326 male; mean age 36.1 ± 15.54 years). The prevalence of bifid MC was 11% (n = 102), with no significant differences by sex (p = 0.069). Proportion of bifid MC was higher among younger patients (p = 0.038). Prevalence of morphological variations of type 1 bifid MC was 7.4% (n = 69), type 2 was 2.3% (n = 23), type 3 was 0% (n = 0) and type 4 was 1.1% (n = 10). Prevalence of retromolar canal was 0.9% (n = 8), with no significant differences by sex (p = 0.893) or age (p = 0.371); of these, 2 (0.2%) cases were forward type and 6 (0.6%) cases were retromolar type. No cases of trifid MC were found. Conclusions: Digital panoramic radiographs are useful for detecting morphological variations of the MC; we were able to identify three types of bifid MC as well as retromolar canals. Proper identification of these variations by an easily accessible examination is important for avoiding possible complications in clinical-surgical practice. (Folia Morphol 2019; 78, 1: 163–170)

Artículos de Investigación

Browse

Filters

Advanced Search

Filter by

Settings

Sort By

Results per page

Search Results